This invention relates in general to body and frame assemblies for vehicles. More specifically, this invention relates to an improved structure for a two-piece bracket for engaging and supporting a front upper control arm and a front spring in much a vehicle body and frame assembly.
Many land vehicles in common use, such as automobiles, vans, and trucks, include a body and frame assembly that is supported upon a plurality of ground-engaging wheels by a resilient suspension system. The structures of known body and frame assemblies can be divided into two general categories, namely, separate and unitized. In a typical separate body and frame assembly, the structural components of the body portion and the frame portion of the vehicle are separate and independent from one another. When assembled, the frame portion of the assembly is resiliently supported upon the vehicle wheels by the suspension system and serves as a platform upon which the body portion of the assembly and other components of the vehicle can be mounted. Separate body and frame assemblies of this general type are found in most older vehicles, but remain in common use today for many relatively large or specialized use modem vehicles, such as large vans, sport utility vehicles, and trucks. In a typical unitized body and frame assembly, the structural components of the body portion and the frame portion are combined into an integral unit which is resiliently supported upon the vehicle wheels by the suspension system. Unitized body and frame assemblies of this general type are found in many relatively small modem vehicles, such as automobiles and minivans.
As mentioned above, in both separate and unitized types of vehicle frame assemblies, the suspension system resiliently supports the vehicle frame assembly on the rotatable wheels of the vehicle. One type of suspension system commonly used in both automobiles and trucks is an independent suspension system. In an independent suspension system, the vehicle frame assembly is supported individually upon each of the wheels of the vehicle. As a result, each of the wheels can move upwardly and inwardly relative to the vehicle frame assembly independently of the other wheels. Thus, when a bump or a depression in the road upon which the vehicle is operated is encountered by one of the wheels, the other wheels are not moved upwardly and downwardly in response thereto. Accordingly, the independent suspension system provides a relatively smooth ride for an occupant of the vehicle.
A typical structure for an independent suspension system includes an upper control arm and a lower control arm that are connected between the vehicle frame assembly and each wheel of the vehicle. The upper and lower control arms are typically generally V-shaped, each having a pair of inwardly disposed ends that are pivotably supported on the vehicle frame assembly and an outwardly extending intermediate portion that can pivot upwardly and downwardly relative to the vehicle frame assembly. The outwardly extending intermediate portions of the upper and lower control arms are connected to respective ball and socket joints that are, in turn, connected to the upper and lower ends of a generally vertically oriented steering knuckle. Thus, the steering knuckle can move upwardly and downwardly throughout a predetermined range of movement relative to the vehicle frame assembly while maintaining its generally vertical orientation. The ball and socket joints permit rotational steering movement of the steering knuckle relative to the vehicle frame assembly, while accommodating a limited amount of relative angular movement between the upper and lower ends of the steering knuckle and the respective upper and lower control arms connected thereto during such upward and downward range of movement.
A wheel spindle extends generally perpendicularly outwardly from each of the steering knuckles, and a hub and wheel assembly is mounted on the outer end of each of the wheel spindles. Thus, the wheels of the vehicle can also move upwardly and downwardly throughout the predetermined range of movement with the steering knuckle relative to the vehicle frame assembly. During such upward and downward range of movement, the rotational axes of the wheels are maintained generally parallel with the road upon which the vehicle is operated. The ball and socket joints allow the wheels to be steered, while continuing to accommodate this upward and downward range of movement of the wheels relative to the vehicle frame assembly.
At each of the wheels of the vehicle, a spring or other resilient mechanism is usually provided to counterbalance the weight of the vehicle and, therefore, normally maintain the steering knuckle (and the hub and the wheel assembly secured thereto) at an intermediate position relative to the overall range of upward and downward movement allowed by the pivoting control arms. Because of gravity, the weight of the vehicle exerts a force that urges the steering knuckle to move upwardly relative to the vehicle frame assembly. The spring, on the other hand, reacts between the vehicle frame assembly and the lower control arm so as to exert a force that urges the steering knuckle to move downwardly relative to the vehicle frame assembly. The spring forces are designed to counterbalance the weight of the vehicle such that the steering knuckle is normally maintained in the predetermined intermediate position relative to the vehicle frame assembly. When the vehicle is driven over a bump in the road, the upwardly directed force exerted against the wheel temporarily overcomes the force exerted by the spring, allowing the wheel of the vehicle to temporarily move upwardly from this intermediate position until the wheel passes the bump. Similarly, when the vehicle is driven over a depression in the road, the force exerted by the spring causes the wheel of the vehicle to temporarily move downwardly from this intermediate position until the wheel regains full contact with the road. In this manner, a relatively smooth ride is provided for an occupant of the vehicle.
As mentioned above, the inner ends of the upper and lower control arms are pivotably supported on the vehicle frame assembly. In the past, a first pair of control arm mounting brackets has been provided on the vehicle frame assembly to pivotably support the inner ends of the upper control arm, and a second pair of control arm mounting brackets has been provided on the vehicle frame assembly to pivotably support the inner ends of the lower control arm. As also mentioned above, the spring mechanism reacts between the vehicle frame assembly and the lower control arm so as to normally maintain the associated wheel of the vehicle in its predetermined intermediate position relative to the vehicle frame assembly. In the past, a spring mounting bracket has been provided on the vehicle frame assembly to provide a reaction surface for the upper end of the spring mechanism. In many instances, the spring mounting bracket has been mounted on the vehicle frame assembly between the pair of the upper control arm mounting brackets. Although this structure has functioned effectively, it has been found to be somewhat inefficient, inasmuch as it requires that three separate brackets be secured to the vehicle frame assembly. This has been found to unnecessarily increase the weight, cost, and complexity of the vehicle frame assembly. Thus, it would be desirable to provide an improved bracket assembly that is adapted to engage and support both an upper control arm and a spring in such a vehicular body and frame assembly that is lighter, less expensive, and simpler than known structures.